(1) Field of the Invention
The present invention relates to a backlight assembly and a display device including the backlight assembly. More particularly, the present invention relates to a backlight assembly that effectively discharges heat generated from a light source therein, and a display device having the backlight assembly.
(2) Description of the Related Art
In general, liquid crystal display devices are often used due to a variety of features, such as light weight, slim shape, low power consumption, full-color implementation and high resolution, for example. Specifically, for example, liquid crystal display devices are utilized in computers, laptop computers, portable digital assistants (“PDAs”), telephones, television (“TV”) sets, audio/video devices and other similar devices. In liquid crystal display devices, light transmission is controlled, based on image signals applied to control switches disposed in a matrix pattern, to display images on liquid crystal display panels of the devices.
However, a liquid crystal display device is not a self light-emitting device, and thus, requires a light source such as a backlight, for example. The backlight for the liquid crystal display device may be an edge type backlight or a direct type backlight, based on a position of the light source in the backlight.
More specifically, in the edge type backlight, for example, the light source is disposed at an end portion of the liquid crystal display panel, such that light emitted from the light source is radiated to the liquid crystal display panel through a transparent waveguide plate disposed below the liquid crystal display panel. The edge type backlight provides good light uniformity, has a substantially extended life span and can easily be included in a thin display device. In general, the edge type backlight is employed in a medium-size or small-size liquid crystal display panel.
On the other hand, in the direct type backlight, light sources are typically disposed below the liquid crystal display panel such that light emitted from the light source is radiated over an entire surface of the liquid crystal display panel. The direct type backlight provides high luminance and can generally be employed in a large-size or medium-size liquid crystal display panel.
In a conventional backlight, a cold cathode fluorescent lamp may be used as a light source. Recently, research has been conducted into using a light emitting diode as the light source, since the light emitting diode has various properties such as long life span, lower power consumption, light weight and thin shape, for example. However, the light emitting diode generates a substantial amount of heat. Therefore, a reliability of electric circuits is degraded, due to an increase in the internal temperature of a backlight assembly caused by heat generated from the light emitting diode. In addition, deformation of parts or cases is caused due to thermal stresses caused by an internal temperature gradient.